The imposter employee. In this most common form of the scam, you get a phone call — or sometimes an email or knock on the door — from a con artist pretending to be an employee of Medicare, a state agency or an official-sounding (but nonexistent) organization such as the National Medical Office.

Whatever the alleged affiliation, you're told you need to be issued a new Medicare card, perhaps one with enhanced benefit options. But first, you're asked to authenticate your identity by providing your Medicare number (which is your Social Security number) and your date of birth.

You may even be asked for a credit card or bank account number, under the guise of covering the cost of the new card or further "verifying" your identity.

Don't respond!

Medicare will not call you asking for your number; it will ask for it only when you contact the agency yourself. And there are no legitimate Medicare agents who will visit your home or send unsolicited emails.

Providing your identifiers to these people is just a set-up for possible identity theft. The requested information is all that fraudsters need to establish new credit accounts in your name. The info can also be used to make bogus duplicate cards for medical identity theft, in which health care services are provided to someone else using your identity.

Refund ripoffs. The scammer tells you you're entitled to a refund for last year's Medicare premiums. All you need to do is verify your identity.

The scammer may claim that your refund must be direct-deposited into your bank account. In fact that's just another lie to glean your account number and possibly drain your checking or savings funds.